[geeks] caffeine - differences based on source

[nate at portents.com]

> Patrick Giagnocavo wrote:
>> Hi
>>
>> Seems when I drink tea, the caffeine stays in the system longer and the
>> effects are distributed over a longer length of time, than when I drink
>> a soft drink that has caffeine.
>>
>> Does that make any sense to anyone?  Anyone observed any differences?
>
> Are you sure it's all the effect of the caffeine?  Tea contains tannic
> acid too.

http://en.wikipedia.org/wiki/Caffeine

"The disparity in experience and effects between the various natural
caffeine sources could be due to the fact that plant sources of caffeine
also contain widely varying mixtures of other xanthine alkaloids,
including the cardiac stimulants theophylline and theobromine and other
substances such as polyphenols which can form insoluble complexes with
caffeine.[15]"

[15] Balentine D. A., Harbowy M. E. and Graham H. N. (1998). in G Spiller:
Tea: the Plant and its Manufacture; Chemistry and Consumption of the
Beverage.